Apparatus and metod for cable connection retention

ABSTRACT

An apparatus and method for preventing inadvertent disconnection of male and female electrical connectors is provided. In one principal type of method and apparatus, devices are configured to provide outside retaining forces to retention prongs of a female electrical connector, substantially restricting or preventing the retention prongs from moving toward an outer non-holding position after connecting with receiving portions in the male connector. In another principal type of method and apparatus, a female electrical connector includes modified retention prongs having a portion configured to enter and remain in surface holes of the male connector so that the male connector, once inserted, cannot be removed from the female connector without a user manipulating the modified retention prongs.

BACKGROUND OF THE INVENTION

[0001] The present invention generally relates to communicationconnections. More particularly, it relates to an apparatus and methodfor retaining a connection between male and female connectors, such asUSB connectors, to minimize the occurrence of accidental disconnectsbetween the connectors.

[0002] Connections using the Universal Serial Bus (USB) standard arebecoming increasingly more commonplace and useful in computer peripheraldevices, audiovisual equipment, and electronic devices in general. Suchdevices have advantages including a simple mechanical connection, anability to connect and disconnect while a device is in operation (“hotplugging”), an ability to connect several devices, and a large selectionof devices using this connection standard.

[0003]FIG. 1 shows typical prior art male 10 and female 12 A-side USBconnectors, also known as A-type or Series A connectors. The principalmechanical and electrical characteristics of these connectors arestandardized according to convention known in the art. The femaleconnector 12 or socket contains a metal connector casing 14 having upper16 and lower 18 surfaces, each surface having a pair of retention prongs20 typically cut and formed out of the resilient metal used tomanufacture the metal connector casing. The retention prongs 20 eachhave a detent 22 for holding the male connector 10, created by bending aportion of the retention prongs inwardly (for the upper surface 16 asshown, downwardly, and for the lower surface 18, upwardly).

[0004] The male connector 10 has a metal connector body 24 connected toa cable 26 for communication with a device. The connector body 24contains upper 28 and lower 30 surfaces, each having a pair of receivingportions, such as typically square surface holes 32, which are alignedwith the detents 22 of the retention prongs 20 of the female connector12 when the male connector 10 is fully inserted. As shown in FIGS.2A-2C, as the male connector 10 is inserted into the female connector 12(FIG. 2A), the upper and lower retention prongs 20 are forced outwardlyfrom an inner resting position to an outwardly flexed position (FIG.2B). When the male connector 10 is inserted to the point where theretention prongs 20 align with the surface holes 32 (FIG. 2C), theretention prongs, being made of resilient material, naturally returninwardly toward an inner holding position and the detents 22 partiallyfall into the surface holes 32, creating a snap fit which retains theconnection. Because the detents 22 of the retention prongs 20 aresomewhat rounded, this type of connection allows relatively easyinsertion and removal (see FIGS. 2D and 2E) of the male connector 10from the female connector 12, while providing a degree of resistance todisconnection.

[0005]FIG. 13 shows a typical prior art B-side male connector 80 and afemale (socket) connector 88. The male connector 80 includes a cable 26and a metal connector body 82 having a pair of side surfaces 84, onlyone of which is visible in FIG. 13. Each of the side surfaces 84includes a vertically extending outward projection 86 having a roundedsurface. When the male connector 80 is inserted into the femaleconnector 88, inwardly extending ends of a pair of rotation prongs 92 onside surfaces 90 (only one side surface is visible in FIG. 13) of thefemale connector engage receiving portions of the male connector on arearwardly facing side (in FIG. 13, the left side) of the projections86.

[0006] The connection is thus retained, but the male connector 80 andfemale connector 88, like the A-side male 10 and female 12 connectors,can be easily connected and disconnected due at least in part to therounded surface of the projections 86.

[0007] However, such ease of connection and disconnection creates aproblem for use in devices where a more secure attachment is desired.For certain electrical devices, it is desirable to connect productseasily, yet keep them from inadvertently disconnecting. In such devices,a user may need to connect the device only once, and not disconnect thedevice unless the device needs to be moved. For these devices a user maynot desire such easy disconnection. Or, the user may wish to have aconnection that provides easy insertion and de-insertion, while alsoproviding a lock to prevent accidental disconnection. Certainenvironments may include positioning of the connected device thatcreates tension on the USB cable. If the device is moved or jostled,even unintentionally, the cable is prone to undesirably disconnect fromthe device.

[0008] Prior solutions to this problem, such as clamps, mounting clipsor other methods of strain relief have proved ineffective to solve theproblem of providing a USB connection that, while easy to connect, isnot too easily disconnected.

BRIEF SUMMARY OF THE INVENTION

[0009] The present invention provides an inventive apparatus and methodfor retaining the connection of first and second electrical connectors,while still allowing a relatively easy connection. The basic concept ofthis invention is to increase a required connector extraction force orlock the connection so the device is not inadvertently disconnected. Thepresent invention retains the connection by, among other things,modifying a device containing a second connector to create a restrainingelement for biasing the retention prongs toward an inner holdingposition, or by modifying the retention prongs of the second connector.

[0010] In one embodiment, a device having a second connector is modifiedto form a restraining element for providing pressure to the retentionprongs, to bias them towards an inner holding position. This restrainingelement may include one or more cutouts forming flexible members in aconnection area of the device surrounding the second connector, and mayhave one or more pairs of contact members supported by the flexiblemembers for contacting the retention prongs.

[0011] In another embodiment, a restraining element in the form of asliding latch may be used in which the sliding latch contains a pair ofelongated legs having teeth and slots. The sliding latch may beslidingly positioned so that either the teeth or the slots are alignedwith the retention prongs. When the teeth are aligned with the retentionprongs, they substantially prevent the retention prongs from moving toan outwardly flexed, non-holding position, thus locking a connection. Ina related embodiment, a second connector can be fitted with a sleevehaving inwardly projecting stops which can be positioned toward theretention prongs, to maintain the retention prongs in their holdingposition.

[0012] In yet another embodiment, the retention prongs of the secondconnector are modified by forming at least one barbed projection whichis acutely angled towards the back of the second connector. The barbedprojection enters the surface holes of the first connector as it isinserted and substantially prevents removal of the first connectorunless the modified retention prongs are separately lifted by, forexample, manipulating a tab connected to the modified retention prongs.

DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is a perspective view of typical prior art male and femaleUSB A-side connectors;

[0014] FIGS. 2A-2E are side views in section along line 2-2 of FIG. 1showing steps of a typical prior art male-female USB connection anddisconnection;

[0015]FIG. 3 is a perspective view of a bottom portion of a devicecasing having a flexible restraining element according to one embodimentof the present invention;

[0016]FIG. 4 is a perspective view of the female USB connector placedover the bottom portion of the device casing shown in FIG. 3;

[0017]FIG. 5 is a perspective view of the assembled device shown in FIG.3 having a flexible restraining element;

[0018]FIG. 6 shows a sliding latch according to another embodiment ofthe present invention;

[0019]FIG. 7 shows a perspective view of a second embodiment of thesliding latch;

[0020]FIG. 8 is a perspective view of a third embodiment of the slidinglatch;

[0021]FIG. 9 is a perspective view of a sliding latch positioned aroundthe female USB connector;

[0022]FIG. 10 is a perspective view of a modified female connectoraccording to another embodiment and method of the present invention;

[0023] FIGS. 11A-11E are top views of a male USB connector beingconnected and disconnected from the modified female connector of FIG.10; and

[0024] FIGS. 12A-12E are side views in section along line 12-12 of FIG.10 of the male USB connector being connected and disconnected from themodified female connector of FIG. 10;

[0025]FIG. 13 is a perspective view of typical prior art male and femaleB-side connectors; and

[0026] FIGS. 14A-14B are perspective views of a modified female B-sideconnector and sleeve holding a male B-side connector in retracted andforward positions, respectively.

DETAILED DESCRIPTION

[0027] One central concept of this invention is to increase a requiredconnector extraction force and/or lock a connection so that a male USBconnector is less apt to be inadvertently disconnected from a female USBconnector. Several of the embodiments take advantage of the property ofretention prongs to extend outwardly from the female connector as themale connector is connected or disconnected, as described above. In manyof these embodiments, to increase the connection force at least aportion of a device casing has been modified or introduced to create arestraining element, supplying outside biasing pressure to the retentionprongs of the female USB connector, thus restricting outward movement ofthe retention prongs. Some of the embodiments may create a constantbiasing force on the retention prongs, while others create a force onthe retention prongs when manipulated by a user.

[0028] To substantially “lock” the connection, other embodiments employmodification of the retention prongs of the female USB connector so thatwhen they enter a pair of surface holes of the male USB connector, theycannot be removed simply by pulling out the male connector withoutsubstantial force unless the user performs a separate action to move theretention prongs, such as lifting or pressing a tab.

[0029] It is to be understood that, while several specific embodimentsare shown and described herein, the concepts and principles of thisinvention are capable of being implemented in any number of embodimentsand devices, and the specifically described embodiments are merelyexemplary.

[0030]FIG. 3 shows a portion of one exemplary design of a restrainingelement for supplying inward pressure to the retention prongs of thefemale USB connector from outside the female connector. A bottom portion34 of a casing of a preferably plastic device 36 contains a flexiblerestraining element 38 in a connection area surrounding a portion of thebottom surface of a typical female USB connector 12 (see FIG. 4). Whileone design for a sample device 36 is shown herein, the flexiblerestraining element 38 can be formed within various other devices. Theflexible restraining element 38 contains at least one, and preferably apair of contact members 42, which are preferably raised and integrallyformed with the body of the device 36. The contact members 42 areconfigured to align with the pair of retention prongs 20 that interactwith the pair of surface holes 32 of the male connector 10. A pair ofpreferably right-angled cutouts 44 in the device creates relief for apair of flexible members 46 that flexibly yet resiliently support thepair of contact members 42.

[0031] As shown in FIGS. 4 and 5, the female USB connector 12 may bepositioned between a flexible restraining element 38 disposed on both atop portion 48 and the bottom portion 34 of the modified plastic casingof the device 36, so that portions of both pairs of the retention prongs20 are aligned with the upper and lower pairs of contact members 42,supported by the upper and lower pairs of flexible members 46. When theflexible members 46 are in their natural (non-flexed) positions, thecontact members 42 contact a portion of the retention prongs 20, such asthe detents 22 or outwardly projecting end portions 50 of the retentionprongs adjacent to the detents. These contacts provide inward pressureto bias the retention prongs 20 towards their inner holding position andin turn resist outward flexing of the retention prongs.

[0032] Thus, in order to force the retention prongs 20 outwardly, eitherfor connecting or disconnecting the male connector 10 from the femaleconnector 12, the male connector must overcome not only the tensilestrength of the retention prongs, but also the resiliency of theflexible members 46 supporting the contact members 42. In this way, thestiffness of the connection is increased, and occurrences of inadvertentdisconnection of the male connector 10 from the female connector 12 arereduced. This is a passive lock, which does not require a separate stepon the part of the user to help retain the connection. This particularembodiment, capable of being implemented in various ways, has anadditional advantage of being inexpensive, since it may be formedprimarily from a relatively simple mold and cutout in the casing of thedevice 36, and it also performs the function of strengthening the USBconnection without modifying the male 10 and female 12 connectors.

[0033] In an alternative embodiment of an apparatus and method forproviding outside force on the retention prongs 20, a selective inwardpressure is exerted onto the retention prongs by a restraining elementin the form of a sliding latch 52, such as the one shown in FIG. 6. Thesliding latch 52 is preferably integrally formed of plastic andgenerally in the shape of a reverse “C”. It has a pair of elongated legs54 connected together by a bridging portion, with the legs having a pairof teeth 56 formed adjacent a pair of slots 58. When the sliding latch52 is moved horizontally, the slots 58 are preferably moved into or outof alignment with the retention prongs 20. The distance between theinner surfaces of the legs 54 is somewhat greater than the size of themale USB connector 10. The sliding latch 52 may alternately be formed ofmetal, and may be incorporated into the housing of the device 36surrounding the female connector 12.

[0034] In use, when the sliding latch 52 is horizontally positioned sothat the slots 58 are aligned with the retention prongs 20, theretention prongs have the ability to move outwardly (flexing normally)from the male connector 10. The sliding latch 52 at this point is in arelease mode, as shown in the device of FIG. 9, allowing normalconnection and disconnection of the male connector 10. The maleconnector 10 is thus inserted into the female connector 12 with atypical insertion force.

[0035] After the male connector 10 is fully inserted and the detents 22are at least partly within the surface holes 32, however, the userslides the sliding latch 52 horizontally (perpendicular to the directionof cable insertion), to position the pairs of teeth 56 over the pairs ofretention prongs 20. When the pairs of teeth 56 are positioned on top of(or underneath) the retention prongs 20, the retention prongs arecontacted from the outside preferably on the end portions 50, and aresubstantially prevented from flexing outwardly from their inner holdingpositions. This holds the detents 22 within the surface holes 32 of themale connector 10, and substantially locks the male connector within thefemale connector 12 (locking mode), preventing inadvertent disconnectionof the male and female connectors. This is an active lock, whichrequires user interaction to lock or unlock.

[0036] Many varied embodiments of sliding latches 52 are possible. Inone alternative embodiment for the sliding latch 52, shown in FIG. 7,the sliding latch contains upper and lower posts 60 for facilitating auser to slidingly manipulate the latch. In the embodiment of FIG. 8, thesliding latch 52 contains an upper movement arm 62 and a pair of lowerposts 60, each lower post having a slot 64 for insertion of a tool or afingernail to more easily manipulate the latch. Other exemplary featuresof the sliding latch 52 may include, but are not limited to, a latchhaving a locking mechanism such as a recess 66 adapted to snap fit witha member (not shown) for retaining the horizontal position of thesliding latch within a device, and a pictorial indicator 68 on thedevice or sliding latch, to indicate for the user the direction of lockand release positions. Other embodiments for a sliding latch may includelegs 54 without slots 58, where the legs are configured to slidefrontwardly or rearwardly (parallel to the direction of cable insertion)to move into or out of contact with the retention prongs 20 of thefemale connector 12.

[0037] A variation of the sliding latch 52 is shown in FIGS. 14A-14B,applied to B-side connectors. The female connector 88 is fitted with asurrounding sleeve 94, which can be made of any suitable material. Thesleeve 94 may be connected to the female connector 88 by, for example,routing out a slot (not shown) on a surface of the female connector. Thesleeve 94 contains a pair (only one being visible in FIGS. 14A-14B) ofinwardly extending stops 96, one on either side of the sleeve. The stops96 shown in FIG. 14A are pins, which are circular in cross-section,though other types of cross-section are possible. One or morecompression springs 98 connect the sleeve 94 to the female connector 88or a portion of a device, and bias the sleeve longitudinally towards itsforward position (in FIG. 14B, leftward). By moving the sleeve 94 from aretracted position (FIG. 14A) to a forward position (FIG. 14B), thestops 96 can be positioned over the retention prongs 92 when theretention prongs are in their holding position, on the rearward (in FIG.14B, left) side of the projections 86 of the male connector 80. Thisholds the retention prongs 92 in place and retains the connection untilthe sleeve 94 is manipulated back towards its retracted position.

[0038] Many alternative embodiments are possible, and are contemplatedby the present invention. For example, the sleeve 94 may be configuredto be rotated (instead of longitudinally slid) so that the stops 96 aremanipulated into and out of alignment with the retention prongs 92. Thesleeve 94 may be connected to a cam (not shown) for manipulating thesleeve. In another embodiment, a catch (not shown) connected to thefemale connector 88 or the sleeve 94 may retain the sleeve in itsretracted position. The catch may be connected to a trigger (not shown),which releases the catch when the male connector 80 reaches a certainpoint within the female connector 88, allowing the compression spring 98to bias the sleeve 94 towards its forward position, to retain theconnection. A release mechanism (not shown) may be connected to thesleeve 94 for allowing a user to manipulate the sleeve to its retractedposition and reset the catch.

[0039] Another method of preventing inadvertent disconnection of themale and female connectors involves modifying at least one of theretention prongs 20 a of the female connector 12 a. In one example of anapparatus implementing this design, shown in FIG. 10, the retentionprongs 20 a are slightly modified to form barbed projections 70 thatextend rearwardly toward the back of the female connector 12 a at anacute angle relative to the plane of the upper surface 16 a of thefemale connector. Each of the retention prongs 20 a are also modified toextend frontwardly beyond the front edge of the female connector 12 a,terminating in a tab 72 that is accessible to the user. The tab 72 maybe the same integral piece as at least one of the modified retentionprongs 20 a, or may be a fitting, such as a plastic fitting, onto theends of the prongs. The tab 72 may be simply positioned outside of themale/female connection, or alternatively may be within its ownencasement (not shown), for easy location and manipulation by the user.The modifications to the retention prongs 20 a may be performed in anymanner known to those in the art.

[0040] FIGS. 11A-11C and FIGS. 12A-12C show top and side views,respectively, of a modified female connector 12 a in various steps ofconnection with the male connector 10. As shown in FIGS. 11A and 12A,the male connector 10 is inserted into the modified female connector 12a in a typical way. As the male connector is inserted further (FIGS. 11Band 12B), the male connector causes the modified retention prongs 12 aof the female connector 12 a to flex outwardly. When the male connector10 is inserted so that its surface holes 32 align with the barbedprojections 70, the resilient retention prongs 20 a move toward theirinner holding positions, and the barbed projections snap into thesurface holes (FIGS. 11C and 12C). However, due to the acute, rearwardangle of the barbed projections 70, the male connector 10 issubstantially prevented from being removed from the female connector 12a. In this way, a one-way locking mechanism is formed such that the maleconnector 10 can be easily inserted into the female connector 12 a, butit cannot be pulled out from the female connector unless the user movesthe barbed projections 70 away from the surface holes 32. The user, toremove the male connector 10 (see FIGS. 11D-11E and 12D-12E), mustmanipulate the tab 72 or tabs attached to the modified retention prongs20 a, by use of a tool, fingernail, etc., and then pull the maleconnector from the female connector 12 a.

[0041] The modified retention prongs 20 a may contain a fulcrum 74disposed between the barbed projections 70 and the tab 72. The fulcrum74 is positioned over the casing 14 of the female connector 12 a. Whenthe male connector 10 is in place, the user is able to unlock theconnection by pressing down on the tab 72 (FIGS. 11D and 12D), thuspressing down on the fulcrum 74 and accordingly lifting the barbedprojections 70 from the surface holes 32. The male connector 10 may thenbe removed (FIGS. 11E and 12E). Thus, upper modified retention prongs 20a can be used while making it easier for a user to manipulate the tab72. Alternatively, the tab 72 may be lifted to unlock the connection.This one-way lock mechanism provides a simple, relatively cost-efficientway to connect, disconnect, and substantially prevent inadvertentdisconnection of a USB cable.

[0042] There has been provided a description of a new and usefulinvention for preventing inadvertent and undesirable disconnection ofmale 10 and female 12 connectors by minimizing or preventing outwardmovement of retention prongs 20 and/or by modifying the retentionprongs. Many alternate embodiments and variations are possible whilekeeping within the spirit of the invention. The various embodiments andmethods described herein may be used separately or in combination withone another. These principles may also be applied to a number ofconnectors such as, but not limited to, A-side or B-side USB connectors,IEEE 1394 connectors, and other serial or parallel connection types ordevices, whether or not they already contain other retention devices,such as thumbscrews.

[0043] While various embodiments of the present invention have beenshown and described, it should be understood that other modifications,substitutions, and alternatives can be made without departing from thespirit and scope of the invention, which should be determined from theappended claims.

What is claimed is:
 1. Apparatus for increasing connection strength in aconnectable device between a first electrical connector and a secondelectrical connector having at least one retention prong for retainingthe first connector, the at least one retention prong being flexiblebetween an inner holding position and an outward non-holding position,the first connector having at least one receiving portion for receivinga portion of the retention prong when the retention prong is in itsinner holding position, the apparatus comprising: at least onerestraining element configured to contact the at least one retentionprong and apply a biasing force to the retention prong toward its innerholding position.
 2. The apparatus of claim 1 wherein said at least onerestraining element comprises at least one flexible member formed into acasing of the connectable device, the flexible member being adjacent tothe retention prong.
 3. The apparatus of claim 2 wherein said at leastone flexible member is formed by removing a portion of said casing toform a cutout portion that is adapted to flex to permit connection anddisconnection of the first connector relative to the second connector.4. The apparatus of claim 1 wherein the first and second electricalconnectors are Universal Serial Bus connectors.
 5. The apparatus ofclaim 1 wherein said restraining element comprises a pair of flexiblemembers having contact members aligned with a pair of retention prongsand in abutting contact with said pair of retention prongs to apply abiasing force to the retention prongs toward their inner holdingpositions.
 6. The apparatus of claim 1 wherein said restraining elementcomprises upper and lower pairs of flexible members having a portionaligned with upper and lower pairs of retention prongs, and configuredto abuttingly contact said pairs of retention prongs to apply a biasingforce to the retention prongs toward their inner holding positions. 7.Apparatus for increasing the connection strength for a connectabledevice between a first electrical connector and a second electricalconnector having at least one retention prong for retaining the firstconnector, the at least one retention prong being flexible between aninner holding position and an outer non-holding position, the firstconnector having at least one receiving portion for receiving a portionof the retention prong when the retention prong is in its inner holdingposition, the apparatus comprising: a sliding restraining latchconfigured to abuttingly contact at least one retention prong of thesecond connector to substantially prevent said retention prong frommoving toward its outer non-holding position.
 8. The apparatus of claim7 wherein said sliding restraining latch comprises a pair of spacedapart elongated legs connected together by a bridging portion, the innersurfaces of the legs having at least one slot portion and at least onetooth portion, said sliding restraining latch being movable between afirst position wherein said slot portion is disposed over a retentionprong of said second connector, thereby allowing said retention prong tomove toward its outer non-holding position, and a second positionwherein said tooth portion contacts said retention prong, therebypreventing said retention prong from moving toward its outer non-holdingposition.
 9. The apparatus of claim 8 wherein said sliding restraininglatch further comprises at least one post for facilitating the slidingof said sliding restraining latch.
 10. The apparatus of claim 9 whereinsaid at least one post has a slot for insertion of a member formanipulating said sliding restraining latch.
 11. The apparatus of claim8 further comprising a locking mechanism for retaining said slidingrestraining latch in one of said first and second positions. 12.Apparatus for increasing the connection strength for a connectabledevice between a first electrical connector and a second electricalconnector, the first connector having at least one surface hole, theapparatus comprising: a modified retention prong connected to saidsecond connector and being flexible between an inner holding positionand an outer non-holding position, said modified retention prong havinga first portion adapted to insert into said surface hole when said firstconnector is inserted into said second connector and said modifiedretention prong is in its inner holding position, said modifiedretention prong being adapted to substantially prevent said firstconnector, once inserted, from being removed from said second connector.13. The apparatus of claim 12 wherein said modified retention prong isadapted to substantially prevent said first connector from being removedfrom said second connector unless a second portion of said modifiedretention prong is manipulated.
 14. The apparatus of claim 12 whereinsaid first portion comprises a barbed projection angled rearwardlytowards a back portion of the second connector.
 15. The apparatus ofclaim 13 wherein said second portion comprises a tab connected to saidmodified retention prong, for allowing manipulation of said tab, to movesaid first portion of said modified retention prong away from saidsurface hole and allowing said first connector to be disconnected fromsaid second connector.
 16. The apparatus of claim 15 wherein saidmodified retention prong contains a fulcrum wherein movement of the tabin one direction causes said first portion of said modified retentionprong to move from said surface hole in another direction, thus allowingremoval of said first connector.
 17. The apparatus of claim 15 whereinsaid tab is integrally formed with said modified retention prong.